1. Field of the Invention
The present invention relates to an image processing apparatus and an image processing method for image processing in a color management system or the like to faithfully reproduce colors.
2. Related Background Art
As shown in FIG. 40, a color gamut is different from device to device, such as scanner, monitor, printer and the like.
In FIG. 40, x and y denote chromaticity coordinates, and the inside of a graphic is a color gamut.
That is, to reproduce colors absorbing a difference in color gamut, a problem is how a color in a nonoverlapping gamut is to be handled.
For example, a monitor color space is to be converted to a printer color space, a problem is which printer color is used to express a color falling in the monitor color space, but not in the printer color space.
A process related to this is called a color gamut compression process (or color space compression process).
A color gamut compression method is the one for mapping image data to colors expressible on an output device and is usually called CMM (color matching method).
However, in a conventional color management system, only one process method is available for implementing the color matching method.
In the color space conversion process between devices such as scanner, monitor, printer and the like, what process including color space compression is to be executed, i.e. a process method does not depend on devices, but information used for a process depends on devices.
The abovementioned information is stored in a file called a device profile.
For example, the profile of a monitor contains data describing monitor characteristics such as x-y chromaticity values of red, green, blue and white, data on gamma characteristic curves for red, green and blue and the like for the monitor.
Device profiles, as shown in FIG. 41, are called scanner profile, monitor profile, and printer profile in correspondence with individual devices.
In the abovementioned color space conversion, a process is executed using a profile corresponding to a source device and a profile corresponding to a destination device. The former profile is called a source profile, and the latter profile is called a destination profile.
For example, in a conversion from the scanner color space to the monitor color space, the source device is a scanner, and the profile of the scanner is a source profile, while the destination device is a monitor, and the profile of the monitor is a destination profile.
The abovementioned method has involved a problem of a failure to execute image processing by selecting a process of realizing one color matching method according to an application.